The present invention relates to a hand operated opener particularly adapted to handle pistachio nuts although it is not so limited in its operation. In the preparation and roasting of pistachio nuts, openings both with small size and long size slots result. The invention according to the present concept has a configuration which will operate on nuts having either the large or small sized openings. A pair of spring biased levers are included which have at their operating ends a shoulder for limiting the initial movement of the opening ends into the nuts whereby damage to the rather fragile pistachio nuts is prevented.
A special feature present in this invention is the dual capability of entering and opening the nut either through a small or through a large opening. With this capability in mind, a small pointed end is provided for opening a small slotted nut while a complementary curved and sharpened portion is provided to open a longer slotted opening that may be present in the nut.
A number of prior art devices are known which attempt to open nuts or otherwise operate in a pivotal opening fashion to achieve a similar end result.
U.S. Pat. No. 3,074,449 was issued on Jan. 22, 1963 to W. Mikulas for "Device for Opening Nuts". The device shown and claimed in that application, however, is of a bar shaped and opening wedge configuration and it does not have the several capabilities of the present invention.
U.S. Pat. No. 1,622,309 was issued to L. C. DeForest on Mar. 29, 1927 for a "Date Pitter" which opener attempted to solve a similar problem to that handled by the present invention. The opener included a pair of pivotally operated end portions with serrated surfaces with in a different manner would tend to engage and spread open the shell halves of the device.
U.S. Pat. No. 2,472,354 was issued on June 7, 1949 to C. P. Waters for "Cocoanut Husk Removing Tool". This patent shows a device adapted to split and open a cocoanut husk in which there is provided a bumper and a pointed end portion for achieving the end result. The device is not adapted to handling nuts of the pistachio type in which there needs to be an accommodation both for small and for large nut slots in the structure of the opener.
U.S. Pat. No. 2,058,072 was issued on Oct. 20, 1936 to J. C. Fiddyment for "Nut Recracker". This patent discloses and claims a black walnut cracker adapted to provide a pivotal and serrated opening end portion opening to a nut of the walnut type.
A plurality of devices are known in the prior art for handling pivotally and resiliently contained arms which, responsive to a manual actuation, will spread or close according to the structure of the devices and either grip or spread the object to be opened.
U.S. Pat. No. 2,634,728 issued on Apr. 14, 1953 to G. T. Dale for "Hair Tweezers" is of interest with respect to this type of construction. It does not, however, have any relationship in its operation or in the end structure of it to handle with equal facility either large or small opening nuts after the manner of the present application.